diff --git a/src/daemon/meta_data.c b/src/daemon/meta_data.c
index b3f892a22061804ef0cfa79de2323dca3b55c7b0..9e4fd07ecfdf99716a11e64532a8ccb6d5654041 100644 (file)
--- a/src/daemon/meta_data.c
+++ b/src/daemon/meta_data.c
**/
#include "collectd.h"
+
#include "plugin.h"
#include "meta_data.h"
-#include <pthread.h>
-
/*
* Data types
*/
return (e);
} /* }}} meta_entry_t *md_entry_lookup */
+/*
+ * Each value_list_t*, as it is going through the system, is handled by exactly
+ * one thread. Plugins which pass a value_list_t* to another thread, e.g. the
+ * rrdtool plugin, must create a copy first. The meta data within a
+ * value_list_t* is not thread safe and doesn't need to be.
+ *
+ * The meta data associated with cache entries are a different story. There, we
+ * need to ensure exclusive locking to prevent leaks and other funky business.
+ * This is ensured by the uc_meta_data_get_*() functions.
+ */
+
/*
* Public functions
*/
int meta_data_clone_merge (meta_data_t **dest, meta_data_t *orig) /* {{{ */
{
- meta_entry_t *e;
-
if (orig == NULL)
return (0);
}
pthread_mutex_lock (&orig->lock);
- for (e=orig->head; e != NULL; e = e->next)
+ for (meta_entry_t *e=orig->head; e != NULL; e = e->next)
{
md_entry_insert_clone((*dest), e);
}
int meta_data_exists (meta_data_t *md, const char *key) /* {{{ */
{
- meta_entry_t *e;
-
if ((md == NULL) || (key == NULL))
return (-EINVAL);
pthread_mutex_lock (&md->lock);
- for (e = md->head; e != NULL; e = e->next)
+ for (meta_entry_t *e = md->head; e != NULL; e = e->next)
{
if (strcasecmp (key, e->key) == 0)
{
int meta_data_type (meta_data_t *md, const char *key) /* {{{ */
{
- meta_entry_t *e;
-
if ((md == NULL) || (key == NULL))
return -EINVAL;
pthread_mutex_lock (&md->lock);
- for (e = md->head; e != NULL; e = e->next)
+ for (meta_entry_t *e = md->head; e != NULL; e = e->next)
{
if (strcasecmp (key, e->key) == 0)
{
int meta_data_toc (meta_data_t *md, char ***toc) /* {{{ */
{
int i = 0, count = 0;
- meta_entry_t *e;
if ((md == NULL) || (toc == NULL))
return -EINVAL;
pthread_mutex_lock (&md->lock);
- for (e = md->head; e != NULL; e = e->next)
+ for (meta_entry_t *e = md->head; e != NULL; e = e->next)
++count;
if (count == 0)
}
*toc = calloc(count, sizeof(**toc));
- for (e = md->head; e != NULL; e = e->next)
+ for (meta_entry_t *e = md->head; e != NULL; e = e->next)
(*toc)[i++] = strdup(e->key);
pthread_mutex_unlock (&md->lock);